ABSTRACT
The optical emission of a light source represents both its purpose, i.e., illumination by either direct or indirect means, and its physical origins, i.e., a self-generated diagnostic. The study of the optical emission of light sources as a lamp diagnostic has, of course, a long tradition. Measurements of atomic and molecular emissions, line shapes, line ratios, line shifts and splittings, etc., have contributed a great deal to our understanding of light sources in respect of composition, temperature, number densities of species, etc., in both steady state and time dependent (ac and pulsed) systems. Recent work in our laboratories, some of which is reported at this meeting, has led us to re-examine the diagnostic potential of optical emission studies in respect of current opportunities to perform such studies with high spectral resolution and high absolute accuracy, and to analyse the data generated both quickly and in high volume. For the purpose of this the talk I propose to refer to these features collectively as High Performance Optical Spectroscopy (HiPOS). The primary focus of the talk is the study of the intrinsic emission of light sources but many of the principles discussed can be extrapolated to studies involving active probing of sources via high resolution laser absorption spectroscopy (LAS) and laser induced lamp emissions such as found in laser induced breakdown spectroscopy (LIBS) and laser ablation induced emissions (LA-AES). THE SOLAR SPECTRUM
To illustrate the measurement and analysis issues involved in HiPOS we can refer to a defining problem in optical emission spectroscopy, the solar spectrum. The emission spectrum of the sun has been studied since the early nineteenth century, however, it is perhaps surprising that the analysis is far from complete. The scope and scale of the problem is illustrated by the spectrum below which is for a 10 nm range only of the solar spectrum in the region of the Balmer-f3 line of H-atom at 486.1342 nm (Fraunhofer L-line) [1].
